Nein.

Während = during oder in
die meisten = most
sich = themselves

Agree Thea (De).

It's also "disassociate", BTW.

In the German, wouldn't the "distanzieren" have to come after "Phase"? Anyway.

To string it all together, I'd probably say:
During this phase, most children disassociate themselves from their parents.

Der deutsche Satz ist holprig:

Während dieser Phase distanzieren sich die meisten Kinder von deren (besser: ihren) Eltern