Stacey Solomon looked gorgeous when she stepped out in one of her new designs on Saturday for her niece's birthday, but she had to quickly make an apology.MORE: Stacey Solomon shares rare video of son Zachary as she reflects on teen pregnancyPosting to her Instagram Stories, the mum-of-four posed for a selfie in one of her brand new In the Style garments - but they weren't supposed to be warn yet.WATCH: Stacey shared a video of her daughter Rose learning to sit upWearing a stunning blue summer dress, she wrote: "Spring summer coming soon…been working for so long on this, I'm excited it's almost here.RELATED: Take a leaf out of Stacey Solomon’s book with this bargain Amazon mopREAD: Stacey Solomon shares new video of baby Rose's milestone moment"I'm sorry" [tagging In the Style founder Adam Frisby] but I've got to go to my sister's for my niece's birthday so I thought this dress was perfect for the occasion." Stacey looking gorgeous in ginghamWe don't blame her, the gingham baby-doll dress suited the ITV star perfectly.She also gave followers a sneak peek of two other gorgeous pieces, which had different summery, floral designs.She wrote: "The first samples of my spring summer collection have just come. I would love to know what you think of the prints.