A number of years ago had a mom who was court ordered to wean for
overnights.  the toddler just learned - milk at mom's, no milk at dad's.
Adjusted fine to the system.  Go  figure....kids do better sometimes than
we give them credit for.  I guess I'm just saying they are pretty resiliant
if secure, early on.  Of course, the best plan would be to not challenge
them in this way (they aren't labeled for who will become disturbed by this
 :-)   Think it is so    sad that "the best interest for the child" is
frequently lost in anger, revenge etc.  If dad truly loved his child in the
selfless way a parent needs to, then he wouldn't ask this of his toddler.
Sincerely, Pat in SNJ