The X Factor star Rebecca Ferguson has secretly given birth after hiding her pregnancy.The 36 year old singer has announced she has welcomed her first child with husband Jonny Hughes in a sweet Instagram post.The reality TV star posted an adorable black and white image of her newborn baby's tiny fingers and arm, with a glimpse of their face too.The tot was lay on bedding printed with an illustrated fish and nature design. "Surprise! Turns out I can keep a secret. Born on Valentines Day," the mum-of-four captioned her post, as she also revealed her little one's birthday.