7 and a half doesnt seem too young. she's at the age where she understands everything. i say take her with u, especially if she's so keen on going. naturally, when ur over there, u will be anxious about her as there are just so many people there and easy to get lost, but just make sure u explain that she needs to stay with u at ALL times and must NEVER walk off. if need be, use a wrist strap or something.
and the jamaraat is much safer now so thats a bonus!
but take extra precautions, make sure she carries ur hotel card n hotel fone number or something with her wherever she goes. explain to her that should she get lost, she can show it to security/police officials, etc. show them to her so she knows what they look like.
give her as much information as possible, about everything and anything.
its just about being prepared. and she will love it! i "befriended" three kids, all siblings, while i was on hajj, we took em out with us, they'd come chill out in our room, we'd playfight, buy treats for em n everything

so masha'allah, u will find a sense of community within ur hajj group and they too will also have their guard up for ur daughter insha'allah.
