The 37-year-old former Spice Girl, who unveiled her latest collection of dresses at New York Fashion Week, told Elle magazine that her baby girl was delighted when she took her round the shops.
'We went into Prada yesterday and she loved it. It was as if she was saying, 'Mummy, I'm home',' she said.
She also joked that husband David was “annoyed” that she was splashing out on designer clothes for Harper.
She said: 'David gets annoyed that I spend more on Harper's socks than his. Of course I do, he's fine with M&S.'
Posh also revealed that Harper is now the apple of her eye – and that she can't bear to spend time away from her.
'I can't leave her alone for a minute, I haven't been out without her since she was born nine weeks ago. She's too wonderful to leave,' she gushed.