13 months is a rough period, based on the many posts we get on this forum coming from that age. On my experience, it had to do a lot with mobility, teething and separation anxiety.
Mobility: they can stand up and walk on their own. Sometimes they do in in their sleep, wake in the middle of their crib standing and FREAK out, so they need mommie's reassurance that everything's ok. IF it's only a mobility issue, by reassuring her and making her go down, she'll be her own self in a couple of weeks.
Teething. this is the tough one, cause molars can take up to 3 months to pop out!!!!!!!! and they're a pain for both, the toddler and the mom, during this period. Trying some oraljel-tylenol/motrin combo before bed does the trick in most angel babies. My ped explained me that angel babies are easily settled and that's why she can be settled by your sight even if she's in physical pain. That is a confusing thing cause you think, it is not possible that she's in pain cause she's ok when she sees me. Check with your ped and if he ok's the meds, try them before bed and let's see if that makes a difference.
Separation anxiety: you said she had trouble going down a few weeks ago, that also could be a sign. It should be treated the same way, with reassurance and minor talk and eye contact.
Good luck!
