Baby crying with other people

Hello mamas!

So my babes is 4.5 months- and gets really upset if someone else is holding her and she cant see me/hear me.

Tonight, she was babysat by my mil for about 2 hours and she cried the whole time! As soon as I got home and held her she was perfectly fine!

I already have a really hard time leaving her and this just breaks my heart! 😭

Any advice/suggestions?