If your 10 month old is only on his second runny nose, then I commend you for a job well done. I usually use a formula called kid-e-well or a formula by 'Herbs for kids" called the yarrow blend. The formula is made from equal parts of echinacea, yarrow, peppermint and elder flower. It is excellent for helping to clear out whatever is causing the congestion.
Personally, I would not use anything like Nasonex on a young child. The secret to flying successfully with an infant is to nurse or bottle-feed on take off and landing, so the ears will adjust to the change in pressure. If you are dealing with a toddler or young child, chewing gum will usually accomplish the same thing.