If you're staying in Rotterdam I can't think of a nicer place to stay than Jannys.
Beautiful light airy house overlooking the river on both sides. Its pretty close to a main road and railway line but both of these are incredibly well camouflaged so you really don't notice them.
We were in Rotterdam for the marathon and Jannys was a perfect base for this and for having a cold beer afterwards.
We stayed as a couple with our 15 month old. She loved the house and the chickens in the garden and watching the boats and the ducks. Janny was really accommodating with providing a beautiful cot, highchair and baby bath. Our baby is just learning to walk so we could keep an eye on her but if you've got a very mobile toddler the steep stairs might be a bit of a worry.
Overall however absolutely excellent and Janny was incredibly friendly meeting us at check in and seeing us off.
Would definitely stay again.