Complex sentence: The initial plan to get her out of the country following their escape failed and it wasn't until 20 years later that they could meet again, when Ivana also first met her sister Sandy, Kevin Dahlgren's mother, who had been born in the USA.
Split into simpler sentences: The initial plan to get her out of the country following their escape failed and it wasn't until 20 years later that they could meet again. This is when Ivana first met her sister Sandy, Kevin Dahlgren's mother, who had been born in the USA.