I’ve always used Piriton for allergies, I’d imagine this would improve hayfever symptoms, if you gave to your daughter. Do the symptoms get worse when you go outside?
I've just seen piriton on the shelf at Morrisons pharmacy age 1plus in a big bottle, try your local supermarket pharmacy or try boots online.
Apparently there is antihistamines liquid for their age, as my GP sign posted me to buy it sometime ago, but some may start from 2years, but a May baby isn't too far off from 2