A sink faucet assembly that includes a sink faucet and a filter faucet combined together into a single unit. The sink faucet is of the single-handle type for mixing hot and cold water and includes a body member, base, or escutcheon mount upon which the filter faucet is attached. The filter faucet includes a faucet body and spout that may dispense filtered water from an undersink filter and it may further include a water filter fluidly disposed between the faucet body and spout. A filter replacement kit is provided in an embodiment that includes a generally inline water filter, an optional water spout, and an elongated hollow tubular stem adapter attachable to the filter faucet body in a generally push-in manner.