Rheumatoid arthritis and childhood inflammatory arthritis can begin at different speeds. Some patients develop clear symptoms over weeks, while others experience a gradual, insidious onset. In children, pain may not be prominent; limping or morning stiffness can be the main clues. A “rapid onset” may reflect an acute rise in inflammation, whereas a “slow onset” pattern can delay recognition and diagnosis. In both cases, the key operational threshold is persistence: swollen joints, morning stiffness, and functional limitation lasting more than six weeks warrant specialist evaluation. With faster presentations, alternative causes such as infection or trauma must also be considered in the differential. Onset speed influences diagnostic strategy, but it does not establish the diagnosis on its own.