Nonetheless, if grandchild key pair 1 incorporates 1 BTC, and grandchild key pair 2 incorporates 2 BTC, may I ship the three BTC whole as a single transaction?
Sure, however not in the way in which you describe it.
Bitcoin, on the protocol degree, doesn’t “belong” to a key. That’s, there is no such thing as a steadiness per handle or per key as an idea.
As an alternative, consider them as cash. Each time you receives a commission, you obtain a separate new “coin”. Every coin has slightly program (the locking script) that determines who’s allowed to spend it. In follow, your cash are ones with a locking script that requires a signature with a key you will have.
The protocol permits creating transactions that spend a number of cash directly. It doesn’t matter whether or not these cash all have the identical handle, or totally different addresses derived from the identical grasp key, or even when they’ve fully unrelated addresses fully. They’re simply a number of cash, and every coin individually requires a signature.
the truth is, nothing prevents a number of individuals from developing a single transaction that spends a number of cash owned by totally different individuals in the identical transaction. That is referred to as a CoinJoin transaction.
If that’s the case, would this seem on-chain to go away from the kid key pair handle from which each are derived?
All HD wallets do is change the way in which a person pockets derive their keys. Different nodes or events on the community have no idea or care the keys are constructed in a associated approach. So long as they have no idea the grasp public key, your keys are indistinguishable from random keys. The one factor seen on chain is that the transaction spent cash that had been beforehand despatched to distinct addresses, however that is the case for nearly all transactions on the community.
If the grasp non-public key was in chilly storage, however one of many youngster non-public keys was not, may the pockets be outlined as a chilly pockets?
This isn’t doable with non-hardened keys. Given a toddler non-public key and the grasp public key, you’ll be able to compute the grasp non-public key, and from that, all different youngster non-public keys.
Thus, you situation is equal to the non-cold system getting access to all non-public keys, and the entire setup could be very a lot not chilly.
With hardened keys, understanding the kid non-public key doesn’t reveal the grasp non-public key, however you lose the benefit of with the ability to compute youngster public keys with out entry to the grasp non-public key.
in both case, I’d not name this a chilly setup. I’d reserve that time period for setups the place no cash are ever on an internet system.
