Copy value from child module to parent module?

Copy value from child module to parent module?

HI, 

In typical one-to-many relationship between two custom modules, Is there a way to copy field value from child module to parent module based on some criteria?

e.g.

Child module
Record    Date           Value
1              1.Feb.18     x
2              3.Feb.18      y
3              2.Feb.19    z

Parent module
Date field:  _______
Value field : ________

Since the child module which record 2 is the newest (based on the date), the value "3.Feb.18" and "y" are copied to Parent module