Growth in the gap

I love the way this plant with its pretty flowers (is it Alyssum?) is growing in a gap in the tiles around the pool. Was it a bird, the wind, an insect that dropped a seed there? Nature continues to amaze me.
A quiet day today - long walk with Coda, and a day on my own as hubby T has his poker weekend! I must admit to binge watching Netflix...and having a good afternoon sleep.