Bougainvilleas are perfect bonsai's too. They last for centuries that their branches would arch and make many lovely designs depending on where they grow. My brother lives hunting century old bougainvilleas in La Union and he made them into bonsai. He was even able to sell them online during the pandemic. Helped him earn a living. He even had a celebrity bought some of his bonsai and other plants like his variegated rubber trees.
He put together four different bougainvilleas in one so when they bloom, wow! Very beautiful because of its four different shades.
Bougainvilleas love our weather so much and they bloom all year round.
Sad to hear about your husband's plant that it died and withered when his sister left. Maybe she was the care taker of the plant and when she left part of the plant missed her so that it died. Well plants do have feelings too, I guess. Hahaha.