A 20 year old mother brings baby Jack for his 8 week baby check. You ask her if she has any concerns about the child’s development so far. Jack is entirely bottle fed and she is worried that within 10 minutes of most feeds he brings some of it back up and appears a little distressed. He is gaining weight sufficiently along the 50th centile (5kg), and was born at term by normal vaginal delivery. There is no history of rash and bowels are opening as normal. On further questioning, you discover that he is taking 150ml per feed over 10 minutes 6 times per day.
You suspect that he is suffering with reflux. Which of the following would be the best recommendation to make at this stage?