Have you considered having a baby abroad?
In most of the New World (from Canada and US to Brazil and Chile), a newborn receives the country's nationality. This is possible due to Jus Soli, which basically says that any child born in a territory gets that state's citizenship.
They could then live, work, and develop in 2 places, with no restrictions.
They could easily choose between 2 sets of public services (healthcare, education, pension etc).
They would have access to more service provides, from banks to suppliers.
Being raised in 2 cultures could mean greater personal development, while having 2 passports means greater freedom to travel the world.
What are advantages would a second citizenship bring about?
Here are some resources on this topic: https://birthcitizenship.com/