Smaller one fell long back, so bigger one is taking care of it.
This is called
#inosculation: when branches or roots of different trees are in prolonged intimate contact, they often abrade each other, exposing their inner tissues, which may eventually fuse.
Observed more in case of same species (especially thin barked ones) but also observed in inter species.
The term is also associated with plastic surgery, one of the method to do that. See nature knew this surgery way before us. That is how this
#TreeTrust works. Wonders of nature.
@SDG2030