The Shulhan Aruch (Orah Haim 225) rules that if one sees a friend whom he had not seen in thirty days or more, and this is a friend for whom he feels great affection, such that the reunion brings him great joy, then he recites the Beracha of "She’hehiyanu." The Mishna Berura (Rav Yisrael Kagan of Radin, 1839-1933) adds that this would apply also to a close family member – spouse, child, grandchild, and so on.

The Hesed La’alafim (Rav Eliezer Papo, 1785-1828) writes that it is not customary to recite "She’hehiyanu" in this situation, because of the prevalence of "Hanufa" ("flattery"). If it were customary to recite this Beracha, people might recite this Beracha upon seeing somebody whom they are not sincerely happy to see, for the sake of flattering that person. Therefore, the custom developed not to recite "She’hehiyanu" upon reuniting with a friend whom one has not seen. This is likely the reason behind the Ben Ish Hai’s ruling that this Beracha should be recited without "Shem U’malchut" (the phrase "Hashem Elokenu Melech Ha’olam") – in order to avoid reciting a Beracha in vain. Hacham Ovadia Hedaya (1889-1969) writes that even according to the view of the Hesed La’alafim, one may recite this Beracha upon seeing a parent, because there is no concern of "Hanufa" when expressing joy and excitement over reuniting with a parent.

In truth, however, all this is immaterial as far as the practical Halacha is concerned, because the Shulhan Aruch clearly writes that this Beracha is to be recited, with "Shem U’malchut." And thus Hacham Ovadia Yosef rules that one should recite this Beracha upon seeing a close friend or family member for the first time in thirty days, as there is no reason not to follow the Shulhan Aruch’s explicit ruling.

The Mishna Berura writes that if one has had contact with that friend over the last thirty days, such as through letters, or a message delivered through a messenger (or, in our days, phone calls or digital communication), then it is unclear whether "She’hehiyanu" should be recited upon being reunited with this friend. Therefore, we apply the rule of "Safek Berachot Le’hakel" – that a Beracha is not recited when its requirement is subject to uncertainty – and the Beracha is not recited. Hacham Ovadia Yosef disagrees, however, noting that this Beracha is recited upon the joy of reuniting with the friend, and thus communication in the interim is inconsequential. According to Hacham Ovadia, then, one recites "She’hehiyanu" even if there was communication within the previous thirty days (which is usually the case in today’s world, where people regularly communicate with one another via telephone or text messages).

The Shulhan Aruch also rules that if one had not seen his friend in the previous twelve months, then upon seeing him he recites not only "She’hehiyanu," but also the Beracha, "Baruch Ata Hashem Mehayeh Ha’metim" ("Blessed are You, Hashem, who resurrects the dead"). As the person was uncertain whether his friend was alive, having not seen him in a year, he recites this Beracha to express his joy over seeing that the friend is indeed still alive. The Ben Ish Hai rules that this Beracha should not be recited, because people nowadays are sensitive, and one may be insulted if his friend recites this Beracha, indicating that he had feared he was dead. Once again, however, the Shulhan Aruch clearly rules that this Beracha should be recited.

As a practical matter, however, it would seem that nowadays, we would, in most cases, not recite "Mehayeh Ha’metim" upon seeing a friend or family member for the first time in twelve months. Rav Yaakob Hagiz (1620-1674), in Halachot Ketanot, writes that since this Beracha is recited because one had been unsure whether his friend was alive, it is not recited if one had communication with his friend during the period when they did not see each other. If they were in contact with one another, then they obviously knew that the other was alive, and so they do not recite the Beracha of "Mehayeh Ha’metim." Accordingly, Hacham Ovadia rules that in the case of friends who had not seen each other for twelve months, they would not recite "Mehayeh Ha’metim" if they had been in contact during those twelve months. As mentioned, "She’hehiyanu" is recited when friends see each other for the first time in thirty days, even if they had been in contact during those thirty days, but "Mehayeh Ha’metim" is not recited unless there was no contact between them for twelve months, which nowadays is quite rare.

Hacham David Yosef raises the question of whether the Beracha of "She’hehiyanu" is recited when reuniting with a friend or family member for the first time after thirty days if the friends or family members had seen each other via video, such as through Zoom or Facetime, in the interim. Hacham Ovadia had ruled that one does not recite "She’hehiyanu" upon seeing somebody via video, but he did not address the question of whether seeing someone via video qualifies as "seeing" such that we do not consider thirty days to have passed since the last time the friends saw one another. This question requires further analysis, and one should consult with their Rabbi for personal guidance.

Summary: If one sees a close friend or family member whom he had not seen in thirty days or more, and seeing this person brings great joy, then he recites "She’hehiyanu." This applies even if they had spoken with another or sent messages during the last thirty days. It is unclear, however, whether this applies if the friends or family members had seen each other via live video within the last thirty days. If two friends or family members did not see each other and also had no contact with one another for twelve months or more (which, in today’s world, is quite uncommon), then upon reuniting they recite not only "She’hehiyanu," but also the Beracha of "Mehayeh Ha’metim."