slow weight gain in a 11 month old

[Swangirl]

I have a 11 month old ds who weights 15lbs he is on the 0.4 centile. He eats well and enjoys a wide range food and is still breast fed.
He is lively active and hitting his developmental milestones.

I was wondering if there is anyway I can get him to gain weight before I go back to get him weight at HV's clinic in a months time.

Is he following the centile line or has he dropped since birth? If he is roughly following the line then I wouldn't worry, how much does he eat?

He has dropped since birth he was on the 50th,centile and slowly dropped.
He eats roughly each day breakfast one wheatabix with milk plus morning breastfeed. mid morning breastfeed lunch ham sandwich, banana drink of juice. mid afternoon breastfeed
Dinner spaghetti with cheese sauce and Vegatables drink of juice

early evening breastfeed
bed time breastfeed

My son has just turned 10 months and I have started giving him snacks inbetween meals, so thats a thought. Also puddings after lunch and dinner. Maybe give the banana as snack mid morning before 2nd breastfeed, then give yoghurt as dessert after lunch, then another snack mid afternoon before 3rd breastfeed and a dessert after his tea. My son has had puddings after meals for almost 4 months now. Other ideas for snacks are rusks, rice cakes, cheese (grated or v.small pieces), fromage frais, toast fingers, fruit/fruit puree. My son won't eat finger foods yet but I'm guessing that yours is if he is having sandwich for lunch :-)

Meant to say that might be too much all in one go so maybe just morning snack and puddings after meals to start with (small amounts) and then gradually increase :-)

He loves feeding himself

He does have snacks during the day but not puddings
I'll try puddings
Thanks