wrap someone (up) in cotton wool
US /ræp ˈsʌm.wʌn ɪn ˈkɑː.tən wʊl/
UK /ræp ˈsʌm.wʌn ɪn ˈkɑː.tən wʊl/

1.
to protect someone too much from danger, difficulties, or unpleasant experiences
:
•
Parents shouldn't wrap their children up in cotton wool; they need to learn to deal with life's challenges.
•
She was always wrapped up in cotton wool by her older siblings, so she never learned to stand up for herself.