Why TCP_Relative_Sequence_Numbers don't start at 0 ?

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I used wireshark to capture a tcp packet. I found out my "relative sequence number" alway equal "sequence Number (raw). Why it don't start at 0??

Transmission Control Protocol, Src Port: 63620, Dst Port: 443, Seq: 1052312681
    Sequence Number: 1052312681    (relative sequence number)
    Sequence Number (raw): 1052312681
    Acknowledgment Number: 0
    Acknowledgment number (raw): 0
    1011 .... = Header Length: 44 bytes (11)
    Flags: 0x002 (SYN)

I add wireshark -v output.

Wireshark 4.0.4 (v4.0.4-0-gea14d468d9ca).

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