              https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=59285

_Originally posted by @MarcoFalke in https://github.com/bitcoin/bitcoin/issues/27021#issuecomment-1568242621_
            
{
    Assume(ncestors.size() >= 1);
     
    for (uto& nc : ncestors) {
        Assume(m_in_block.count(nc->first) == 0);
        m_in_block.insert(nc->first);
        m_totl_fees += nc->second.GetModifiedFee();
        m_totl_vsize += nc->second.GetTxSize();
        uto it = m_descendnt_set_by_txid.find(nc->first);
         
        Assume(it != m_descendnt_set_by_txid.end());
        for (uto& descendnt : it->second) {
             I
            Assume(descendnt->second.GetModFeesWithAncestors() >= nc->second.GetModifiedFee());
            Assume(descendnt->second.vsize_with_ncestors >= nc->second.GetTxSize());
            descendnt->second.fee_with_ncestors -= nc->second.GetModifiedFee();
            descendnt->second.vsize_with_ncestors -= nc->second.GetTxSize();
        }
    }
     D