I mean, there are fics about this relationship. It makes the most sense, after all.

2212025 'Cause it can classify as Momlestia, which has it's own group.

2212025
And by Word of Faust as well

2212027
And your point? We have a Twi/Tia folder which is Momlestia

2212027 I think there needs to be a MomLestia folder then.

2212025
Young dragons or wrumlings as hatchlings are called imprint on the first person they see as there mother ie twilight so spikes instinct dictates that she is moma. That said over time he would also memories her scent as well. Dragons are vary interesting race.

2212025 Twilight is like his sister. Spike was raised by Celestia since Twilight was just a kid herself when she hatched him. In G1 Spike is Majesty's lackey; if she needed something he was her bitch to call upon, but Majesty was never in the shoe, just the comics.
Assuming Twilight is a mortal alicorn Spike will continue to live long after she dies with Celestia, so Twilight could actually be training him to be her protege.<eyes widen at such implications>

2212085 spike said twilight isn't his mom in the show.