Only time will 'heal the rift/breach' between the two families. [=make the two families become friendly again]
The tree sap is believed to have 'healing' powers.
After the divorce, he needed some time to 'heal'.
(..) It comes out of a... ...particularly painful part of our history. Yes. Yes. But it's been a way we've been able to heal. At first it was a reminder of the rebellion It was the price the Districts had to pay. But I think it has grown from that. (..)2012 The Hunger Games