Head of Household

My fiancee, her 2 children (10 & 6), and I lived together for the entire year (2023). I provided more than half support for all three of them. My fiancee received a small inheritance (around 16k) from her great grandfathers trust and only worked a couple of days in 2023. We filed each filed an extension because we were waiting for her K1 to arrive for her inheritance. The K1 is only for a few hundred dollars and her W2 is only a couple of hundred dollars, so we believe she is not required to file a tax return of her own. Do I qualify for head of household status if I claim the three as dependents? It doesn't appear the turbo tax program is offering that as a filing status for my situation if so.