  "mempoolminfee": 0.00000000

When the minrelaytxfee is > 0.

{
    if (request.fHelp || request.params.size() < 1 || request.params.size() > 2) {
        throw std::runtime_error(
            "getmempoolancestors txid (verbose)\n"
            "\nIf txid is in the mempool, returns all in-mempool ancestors.\n"
            "\nArguments:\n"
            "1. \"txid\"                 (string, required) The transaction id (must be in mempool)\n"
            "2. verbose                  (boolean, optional, default=false) True for a json object, false for array of transaction ids\n"
            "\nResult (for verbose=false):\n"
            "[                       (json array of strings)\n"
            "  \"transactionid\"           (string) The transaction id of an in-mempool ancestor transaction\n"
            "  ,...\n"
            "]\n"
            "\nResult (for verbose=true):\n"
            "{                           (json object)\n"
            "  \"transactionid\" : {       (json object)\n"
            + EntryDescriptionString()
            + "  }, ...\n"
            "}\n"
            "\nExamples:\n"
            + HelpExampleCli("getmempoolancestors", "\"mytxid\"")
            + HelpExampleRpc("getmempoolancestors", "\"mytxid\"")
            );
    }
    bool fVerbose = false;
    if (!request.params[1].isNull())