Parent TX (successfully mined):
% bx fetch-tx 4c52f6c486b7e3372d0dc900aa041fcb0c390c89539a4af1ee9b55e9b78fd759
Child TX (appears to be in mempool) that is trying to spend UTXO index 1 (CSV-P2PKH) from parent appears to hang:
% bx fetch-tx 7fba79ad9511a0f27863b712d186c297843cb182569db0aded5d34ff1ca28809
Locktime associated with CSV had to be little-endian encoded. The nSequence of the transmitted child was not little-endian encoded.