> The 18-55 is fine for daylight but as soon as I try to take photos of my kids running around the house in the evening its just a blurry mess I remember having the exact same issue when I was trying to document family holidays with a slow zoom. Initially, I picked up the Fujifilm Fujinon XF 35mm f/2 R WR thinking it would be the fix, but the field of view was honestly too narrow for my living room. You might want to consider the Fujifilm Fujinon XF 23mm f/2 R WR instead because it is much more versatile for indoor candid shots. Be careful with the f/2 aperture tho. While its better than the kit lens, it might still struggle if your lighting is really dim. I would suggest looking into the Viltrox 23mm f/1.4 AF Fuji X as it fits your budget and gives you even more light. Just make sure to update the firmware so the autofocus stays snappy for the kids.

• Sigma 30mm f/1.4 DC DN Contemporary: Finally caught my kids mid-sprint indoors.
• Tokina atx-m 33mm f/1.4 X: Unfortunately, the autofocus felt kinda sluggish during my tests.

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Just found this today and wanted to jump in because kids are basically blur-monsters.

• Quick question tho: are you usually shooting in small rooms or larger open spaces?
• Be careful with used gear before a big trip. I once bought a bargain lens that had a wonky motor and it ruined my vacation photos.
• My current setup taught me that fast glass is useless if the autofocus is too slow for toddlers.

Big if true