Ysolda (wife) clothes not showing in inventory?

I have just aquired the perk that allows me to pickpocket equipped items, but when I look in my wife ysolda's inventory, her clothes are not there? Only her iron dagger is equipped?

I want to put some different clothes on her but she won't equip them when I place them into her inventory, and there are no clothes to take from her either.

Does anyone know why this is? Thanks