Mould in toddlers room

[Stealthynamechange]

hi all

I live in rented. My toddlers bedroom has 2 external walls. I keep finding mould on the external wall by his bed despite having window open daily. Ive cleaned it off (again) im wondering if i should move his bed? But then it would be in the middle of the room or next to radiator.
The house gets lots of condensation, every morning i have to wipe all the windows down. Ive got those little dehumidifer things as well but cant afford to have an electric one running all day.
Ideas needed please.

Definetly report it to the landlord.
Can you safely spray vinegar on the wall?
It kills mould and perhaps it helps better to keep it away then whiping it away

Thanks all, ive reported to lettings agent & moved bed.

To answer questions the boiler is in the loft, no idea about water tanks (im scared of heights & just cannot get into loft).
I really think lack of ventilation is the problem.

No obvious water or damp anywhere.

That wall is cold, but not wet.

I had a corner bedroom with tw external walls

I fitted a bigger radiator

made sure vent was set to open in wall

put wooden blocks against wall to stop bed going or resting against the wall

put bed by radiator wall

it still got a little bit of mould but not much

I would suggest asking your landlord to install a PIV (positive input ventilation) unit.

Basically it sits in your loft and gently pushes fresh air into your house through a vent in the ceiling below the loft. The old damp air will be pushed out of any small openings eg window vents or gaps around old windows. If there are no vents or gaps at all then you might need an airbrick or similar installed somewhere.

It’s not that expensive and in the long run will be cheaper for your landlord than sorting out problems caused by damp (point this out!)

Another nod here for meaco dehumidifiers , we have 2 one in the utility for drying clothes and one in the hallway, Never get any condensation and they also help keep the humidity down in summer.