Thanks for sharing your concern.
Do not worry at all.
The tooth that she has pulled easily is her deciduous tooth,(milk tooth).
underlying there is permanent tooth which will arise through that same place in her jaw.
Do not worry about the hanging gum until it is too un comfortable for her.in that case she has to visit dentist
and get it excised.
Otherwise normally if it is fine with her then just put her on warm saline rinses thrice daily and the tissue will get back to normal again.
Be sure there is no roots inside,as the roots are already resorbed,and thats the reason why she was able to pluck that tooth.
Do not worry.
Do let me know if any query.