Turn back to?

[bosun]

In the following sentence, what does it mean by turn back to? (Does it mean come back to or depend on?

in later life, brothers and sisters often turn back to each other for a special affinity and link to the past.

Also, what does it mean by special affinity ?

looking forward to your reply and always thanks for your assistnace!

[sandhya.sha]

In the following sentence, what does it mean by turn back to? (Does it mean come back to or depend on?

in later life, brothers and sisters often turn back to each other for a special affinity and link to the past.

Also, what does it mean by special affinity ?

looking forward to your reply and always thanks for your assistnace!

Turn back here means 'to come closer to each other'
special affinity is special bond or closeness

[mykwyner]

Also, turn back implies that they drift apart, then get back together.