My small 3 kg cat ate a couple of peanuts — does her tiny size make this more dangerous?

Yes, a small cat's size does increase the risk because even a few peanuts represent a larger portion of her daily intake. The high fat content can more easily trigger pancreatitis in a tiny pet, and salt can cause dehydration faster. Watch closely for vomiting, diarrhea, or lack of appetite over the next 24 hours. For a cat this small, it's best to avoid peanuts altogether in the future. If she shows any signs of illness, contact your vet promptly.