Duchess of Cambridge: Moment Kate Middleton nearly gave the game away The Duchess was caught on camera saying: 'Oh is this for our d...' She stopped herself mid-sentence as she was handed a gift Kate questioned by crowd on whether she was going to say daughter She smiled and wagged her finger and said they did not know Made the apparent slip-up during walkabout in Grimsby yesterday Paddy Power has already paid up to people who bet baby would be girl Other bookies have slashed odds and some have suspended betting The moment the Duchess of Cambridge appeared to give the game away about the sex of her unborn baby has been caught on camera. The famously discreet royal appeared to briefly drop her guard when she was given a teddy bear by a well-wisher during a walkabout in Grimsby yesterday. As she was handed the toy, the Duchess, who is five months pregnant, was caught on camera by Sky News saying: 'Oh is this for our d...' before stopping herself mid-sentence. Hint: The Duchess of Cambridge said 'Is this for our d...' as she was handed a teddy bear by a well-wisher Smile through it: Kate seems to try to gloss over her first sentence by continuing to thank the woman Out of the bag? Kate is questioned by members of the crowd as she continues to walk along the line of well-wishers. Sandra Cook asks her: 'Did you say my daughter?' She then immediately regains her composure and continues to thank the woman for the gift. However, her comment did not go unnoticed by other members of the 2,000-strong crowd who had gathered to catch a glimpse of the Duchess. Duchess of Cambridge, as she is handed a teddy bear: 'Oh is this for our d.... [brief pause] Thank you so much. It is very, very sweet of you. Continues to walk along the line of well-wishers Sandra Cook: 'Did you say "my daughter"?' Duchess of Cambridge: 'No, my. Oh, my? [Wags finger] Oh, no, no, no. I'm sure, I'm sure. We don't know, so...[looks at the ground]' As Kate continued up the line, Sandra Cook, 67, asked: 'Did you say my daughter?' The Duchess initially looked confused but when she realised what Ms Cook meant she smiled and raised an eyebrow before wagging her finger and saying 'no, no, no'. The royal then looked at the ground and appeared to blush as she laughed off the comment. She then told Ms Cook "we don't know, so..." before her sentence tailed off and she changed the subject. Ms Cook then recounted the brief discussion. Slip up? Kate appeared slightly flustered when she was questioned but immediately regained her composure Secret's out? Kate wagged her finger and appeared to blush as she denied she was about to say 'daughter' Blushes: Kate said she and Prince William do not know the sex of the baby before looking at the ground However, the apparent slip-up has been enough to convince large bookmakers in the country. Paddy Power has already out a four-figure sum to punters who had bet on the royal baby being a girl. A spokeswoman said: 'Punters have always fancied a girl and that's where the bulk of the money has gone.' William Hill said it was forced to suspend the market at 10pm yesterday after people rushed to place bets on the baby being a girl. A company spokesman said they may open betting again but believes there 'is a chance' an announcement on the sex of the child will be made in the next 24 hours. The Duchess' words has also prompted Ladbrokes to slash odds on the baby being a girl from 4/5 to 1/2. Jessica Bridge of Ladbrokes said: 'Kate's dropped the biggest hint yet, and the odds have followed suit. 'We'll have egg on our face if their newborn turns out to be a boy, but we're confident there will be a new Princess in the Royal family this summer.' At the end of the visit, Kate was given a bouquet by 11-year-old Evie Oxley, whose fireman father is being treated for cancer and whose mother was recently given the all-clear from breast cancer. Kate was on what the palace call a 'royal away day' in north east Lincolnshire - a chance to cram in as many engagements as possible in a particular area of the country. As well as visiting the fishing museum, which commemorated the town's trawling industry, and the fire station, the Duchess also unveiled a plaque at the Havelock Academy.