CyberMothD
"@TheAmazingPeanuts":/images/2142090#comment_8563424
We may not have numbers, but we do have a good amount of relevant contextual information. We know Gabby being a supporting character for the crusaders means she was likely intended to be in the same generational area, though probably a couple years older given her responsibilities later. We can infer the crusaders are slightly older than spike as Applejack's parents are already out of the picture when she got her cutie mark. We know Spike is explicitly per-pubescent until season 8. While not a perfect fit, both cutie marks and the first molt are general analogs to the start of puberty, and since the show generally follows human scaling it's not unreasonable to assume Spike and Gabby have an age gap probably measuring somewhere in the 2-3 year range, where Spike and Rarity's gap is likely in the 12-13 year range.
We may not have numbers, but we do have a good amount of relevant contextual information. We know Gabby being a supporting character for the crusaders means she was likely intended to be in the same generational area, though probably a couple years older given her responsibilities later. We can infer the crusaders are slightly older than spike as Applejack's parents are already out of the picture when she got her cutie mark. We know Spike is explicitly per-pubescent until season 8. While not a perfect fit, both cutie marks and the first molt are general analogs to the start of puberty, and since the show generally follows human scaling it's not unreasonable to assume Spike and Gabby have an age gap probably measuring somewhere in the 2-3 year range, where Spike and Rarity's gap is likely in the 12-13 year range.