The Roman Festival of Caristia. (sometimes known as Cara Cognatio) was a Feast Day celebrating family reunion. It was when Roman fathers paid special attention to their families, if they were home. This was unusual because many were soldiers as thus away on campaigns and of course because chauvinism was rife at this time. It was a private family festival when families would gather together to celebrate the love of family with banquets and gifts and offer food and incense to the Lares (their household gods). It was a day of reconciliation, when disagreements were set aside.

The poet Ovid satirically wrote at the time that this could only be achieved by excluding family members who caused trouble. It was also an opportunity to put disagreements aside and hopefully reconciled even if it was only to agree to differ. 

It was a celebration of the living family as it continued into the present and the future, because it followed the celebration of Parentalia, which was 9 days of remembrance for family who had passed on which ended the evening before on 21st February. For Parentalia and other celebrations of the dead see here. https://joylina.com/articles/ancient-festivals/ancient-and-modern-festivals-of-the-dead-around-the-world

Did this festival last into the Christian era?

The Cara Cognatio was celebrated long after the Roman Empire had become Christian. It appeared in the calendar in 354, and in 449 AD. Most Roman public festivals were only allowed to take place on odd number days. Seeing this was a private festival it was allowed to take place on an even date. Numbers where very important in ancient Rome.  

The image is Roman fresco from the Lararium of the house of Lulius Polybius (IX 13,3) in Pompeii.