Opposable Thumbs

This is going to seem like a strange question but are your babies thumbs clearly opposable?

My mum was visiting for Christmas and commented that my Daughter grasps things strangely. She doesn't seem to wrap her thumb around anything but instead has more of a crab claw like grasp.

I have an older daughter but I can't remember whether at 6 months she was clearly bending the tip of her thumb.

It wouldn't be a big surprise if she can't bend them as I don't have opposable thumbs and was born like that, weird I know. But I'm just curious if it's something no babies can do at this age!

Ps I will try and add some photo examples tomorrow when she is awake.