'Find my iPad' setup help

First - apologies for what I'm assuming is an easy question, but I've spent a while searching & can't find a useful answer/one that fits my situation.

I have an iPhone & iPad and successfully set-up the 'find my...' on both using my iTunes account.

My problem is that I have just bought my Mom an iPad and want to be able to see hers using my phone, in case she loses it (yes, she does know I'm trying to do this!)
She has her own iTunes account set up in her name, will this prevent me from 'linking' the two together?
If it is possible then could you describe the steps/link me to a post that answers this (that I couldn't find)

Thanks in advance if anyone can help!