Girls, hi! Who is knowledgeable in this matter, could you please tell ...

Girls, hi! Who is knowledgeable in this matter, could you please tell me? I'm on maternity leave until 1.5 years old (it ends in June 2022), pregnant with twins. It turns out from maternity leave to maternity leave. The PNDR is at the end of May, 30 weeks when I should submit a sick leave certificate will be in March. It turns out that benefits for one child will stop being paid as soon as I submit a certificate for two pregnancies. Question - can I provide certificates only then when my first maternity leave ends? By that time, I will actually have two children. Will they pay me for two sick leaves? I hope I explained it normally.