The Family Man is Masako Tale 6 of 9, an Act 2 side tale that starts at Omi Monastery in Kubara. You talk the monk Junshin into revealing where a former Adachi retainer lives, then go after him. It rewards the Charm of Ferocity and 2 Silk.
Part 6 of 10 in Masako's Tales
Part 22 of 66 in Tales of Tsushima
You arrive to find Masako arguing with Junshin. She believes Kajiwara recruited the killers. Junshin knows where he is but will not say, because he thinks Masako is out for blood and Kajiwara is just a humble fisherman. Jin promises it will only be a conversation, and Junshin gives up the location. On the ride to the beach hut, Masako explains why she threw Kajiwara out of her service.
Talk to Masako, then Junshin, then Masako again. Ride with her to the beach hut. Clear the Mongols. Search the hut. Track the footprints away from it.
Mongols have already found the hut, so you clear them first. Inside, there is far more money than a fisherman should have, and his wife and daughter are dead by his own hand. You track Kajiwara down and he admits his part in the plot. Masako executes him. He never knew who was really in charge, so the mastermind is still unnamed.
The Traitor
The Traitor is Masako Tale 4 of 9 and the last Act 1 part of her hunt, set in Ariake. You use a supply map and a monk's help to corner Sadao at a lighthouse. It rewards the Charm of Incineration, the Warrior's Bounty Dye Kit and 2 Silk.
The Conspirator
The Conspirator is Masako Tale 8 of 9, an Act 2 side tale in the Kushi Grasslands where Masako turns her suspicion on Junshin. It ends with a duel against Masako herself and rewards the Charm of Dual Destruction II and the Seasons of War Armor Dye.
The Thief
The Thief is Masako Tale 7 of 9, an Act 2 side tale near Kawamata Village in Kushi. You track Mai, a former Adachi servant who looted the estate after the massacre, and recover the stolen heirlooms. It rewards the Charm of Bludgeoning and 2 Silk.
Image: Sucker Punch Productions / PlayStationThe Tale of Lady Masako
The Tale of Lady Masako is the Act 1 story tale where you recruit Masako Adachi after her clan is wiped out. It rewards the Samurai Clan Armor and is also Masako Tale 1 of 9, opening her side storyline.