In my experience, you dont need to spend a fortune for reliable results. Over the years many units have crossed my desk, but for your T3i, I suggest this:

• Get the Godox TT685II-C TTL Speedlite for Canon because its very dependable.
• Use TTL mode so the camera handles the power for you at the party.
• It fits the hot shoe on top perfectly. Its well within your budget.

Just saw this. Reminds me of my first gig with a T2i back in the day... I spent the whole night at my cousins wedding blasting people in the face with direct light before someone showed me how to swivel the head and bounce it off the ceiling. Totally changed the game for me. If you want something decent that fits your budget:

• Look at the Yongnuo YN600EX-RT II Wireless Speedlite for Canon because it gives you a lot of power for the money.
• Seriously, get some Panasonic Eneloop AA 4-Pack Rechargeable Batteries too or you will go broke buying disposables. Check out the Strobist blog (specifically Lighting 101) if you want to understand the tech side without getting a headache. For the party, just point the flash at a white ceiling and use TTL mode. It makes the light way softer and more natural than that awful pop-up thing on the camera.

> My budget is like maybe 120 bucks max since I am just starting out. Just getting caught up here. Quick clarification tho... are you shooting in a big hall or just a house? Ceiling height changes everything when you're bouncing light for a birthday party. I've been really satisfied with the Canon Speedlite 430EX II for this kind of setup. You can find them used for like 70 bucks and the reliability is way better than the cheap clones. It integrates perfectly with the T3i menu system too. If you gotta buy new, the Neewer NW670 E-TTL Flash for Canon is simple and stays way under your 120 limit. Just make sure you grab some Powerex 2700mAh Rechargeable AA NiMH Batteries so you arent waiting ten seconds for the flash to recharge after every shot. Standard batteries just wont cut it for a busy party.

Jumping in here because I have been super satisfied with my older setup for years and it still works well for these kinds of family events. Re: 'Just saw this. Reminds me of my first...'

• Julia is spot on about bouncing the light, but I kinda disagree about needing a brand new high-end flash right away. You can honestly save a ton of money by looking at older used gear that still supports the automatic features of your camera. To give you the best cost-conscious advice, I have a couple questions:
• Is the party gonna be in a normal house with white ceilings or at a bigger venue with high or dark ceilings?
• Are you planning on making photography a long-term hobby, or do you just want better shots for this one specific night? Knowing those details makes a huge difference in what you actually need to spend. I am happy to point you toward some simpler options once I know the vibe of the room and if you want something that will grow with you or just get the job done next week.